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Taxonomic revision of species of Haematoloechus Looss, 1899 (Digenea: Plagiorchioidea), with molecular phylogenetic analysis and the description of three new species from Mexico
No full textLeón-Règagnon, Virginia, Topan, Janet (2018): Taxonomic revision of species of Haematoloechus Looss, 1899 (Digenea: Plagiorchioidea), with molecular phylogenetic analysis and the description of three new species from Mexico. Zootaxa 4526 (3): 251-302, DOI: 10.11646/zootaxa.4526.3.
FIGURE 5 in Taxonomic revision of species of Haematoloechus Looss, 1899 (Digenea: Plagiorchioidea), with molecular phylogenetic analysis and the description of three new species from Mexico
No full textFIGURE 5. Haematoloechus caballeroi (Skrjabin & Antipin, 1962), from the Tlaloc´s leopard frog, Rana tlaloci Hillis & Frost (Ranidae), from Xochimilco, Mexico. Male terminal genitalia; female proximal genialia. Ventral view; AU = ascending uterus, DU = descending uterus, GP = genital pore, ED = ejaculatory duct, MG = Mehlis gland, OS = oral sucker, OV = ovary, PH = pharynx, SR = seminal receptacle, SV = seminal vesicle, VD = vitelline ducts, VS = ventral sucker. Scale bar = 0.5 mm.Published as part of León-Règagnon, Virginia & Topan, Janet, 2018, Taxonomic revision of species of Haematoloechus Looss, 1899 (Digenea: Plagiorchioidea), with molecular phylogenetic analysis and the description of three new species from Mexico, pp. 251-302 in Zootaxa 4526 (3) on page 259, DOI: 10.11646/zootaxa.4526.3.1, http://zenodo.org/record/261161
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Haematoloechus mexicanus León-Règagnon & Topan 2018, n. sp.
No full textHaematoloechus mexicanus n. sp. (Figs. 10 & 11) Type host: Montezuma leopard frog Rana montezumae (=Northern leopard frog R. pipiens Schreber and R. montezumae of Caballero 1941). Type locality: Ciénaga de Lerma, Estado de Mexico, Mexico. Site of infection: Lungs Holotype: CNHE 10489 Paratypes: CNHE 10490, 10491, 10492. Etymology: Species name refers to Estado de Mexico, the province of the type locality. Other hosts and localities: Mexico: Montezuma leopard frog Rana montezumae, Xochimilco, Mexico City (Caballero, 1941, as H. medioplexus); Patzcuaro leopard frog R. dunni, Pátzcuaro, Michoacán (León-Règagnon et al. 1999, as H. coloradensis); Transverse Volcanic leopard frog R. neovolcanica, Cointzio, Michoacán (this study). Description: Based on 17 mature specimens: Body slender, with thinner anterior region; 4.8–8.3 (7.0) mm long, 0.7–1.3 (1.0) mm of maximum width at testicular region. Tegument covered with abundant thin spines, easily lost during fixation; 7.5–12.5 (9.8) long. Oral sucker subterminal, round, 203–350 (284) long, 180–380 (278) wide. Pharynx oval, 140–280 (206) long, 122–220 (183) wide; oral sucker/pharynx ratio 1: 0.74–0.90 (0.83). Anterior border of pharynx and esophagus surrounded by gland cells. Esophagus 41–200 (129) long. Ceca bifurcated at 390–770 (609) from anterior extremity. Ceca terminate blindly near posterior extremity. Ventral sucker small, weakly developed, frequently obscured by uterus, 52–125 (82) long, 57–130 (84) wide, at 1.5–3.0 (2.4) mm (31%– 41% (37%) of BL) from anterior extremity. Sucker length ratio 1:0.28–0.38 (0.33). Testes 2, elliptical, elongate, oblique, posterior to ovary; distance between ovary and anterior testis 350–825 (548). Anterior testis opposite to ovary, 365–1,080 (778) long, 243–600 (451) wide. Posterior testis 422–1200 (863) long, 260–830 (495) wide. Cirrus sac reaches anterior border of ventral sucker, mostly obscured by ascending uterus; internal seminal vesicle, elongate, slightly coiled. Ejaculatory duct weakly muscular, 150–160 (155) long, surrounded by prostatic gland cells. Ovary kidney shaped, lobed, 320–840 (623) long, 162–500 (342) wide; at 1.8–4.3 (2.8) mm (35%–57% (40%) of BL) from anterior extremity. Seminal receptacle posterior, partially overlapped with ovary; 300–1000 (644) long, 250–590 (410) wide. Mehlis gland dorsal to seminal receptacle. Laurer’s canal not observed. Vitellaria in clusters of oval, well defined follicles, distributed laterally, dorsally invade space between ceca in anterior region of ovary and sometimes in post-testicular region. Anterior limit of distribution 982–3200 (1766) (19%–49% (25%) of BL) from anterior end. Follicles extend asymmetrically, to anterior region of posterior testis on ovarian side of body, and halfway between posterior testis and posterior end of body on side opposite to ovary. Uterine loops fill intra- and extracecal space, partially overlap testes and ovary. Descending part of uterus form several diagonal loops that frequently bend anteriorly or posteriorly and form short longitudinal extracecal loops on ovarian side of body. Uterus forms two longitudinal uterine loops on each side of posterior end of body that reach halfway between posterior end and posterior testis; one loop is frequently shorter. Ascending part of uterus forms diagonal loops on side opposite to ovary, frequently bends anteriorly or posteriorly to form longitudinal extracecal loops. Descending and ascending parts of uterus in two lateral fields rarely invade each other. Distal uterus fills intracecal preovarian region with diagonal loops. Genital pore median, ventral to middle region of pharynx. Eggs dark brown, 22–26 (24) long, 14–20 (17) wide. Excretory vesicle not observed. Excretory pore terminal. Remarks: Haematoloechus mexicanus n. sp. resembles those species of the genus possessing short longitudinal or diagonal uterine loops not reaching the posterior testis, namely H. aubriae, H. caballeroi, H. danbrooksi, H. fuelleborni, H. humboldtensis, H. illimis, H. kernensis, H. occidentalis n. sp., H. pukinensis, and H. veracruzanus n. sp. It also resembles those species with a ventral sucker less than half the size of the oral sucker, namely H. combesi Batchvarov & Bourgat, 1974, H. danbrooksi, H. darcheni Combes & Knoepffler, 1967, H. floedae, H. leonensis (Williams & Coker, 1967), H. medioplexus, H. meridionalis, H. nicolasi, H. ocellati Gassmann, 1975 and H. parviplexus (Table 2). This new species differs from H. caballeroi, H. fuelleborni, H. humboldtensis, H. illimis, H. kernensis, H. occidentalis n. sp., H. pukinensis, and H. veracruzanus n. sp. in the size of the ventral sucker compared to the oral sucker, which is smaller in H. mexicanus n. sp. (1: 0.5–1.0 in the other species vs 1: 0.33 in H. mexicanus n. sp.), and it differs from H. aubriae in the presence of ventral sucker, which is absent in that species. It also differs from H. aubriae, H. caballeroi, H. fuelleborni, H. humboldtensis, H. kernensis, H. occidentalis n. sp., H. pukinensis, and H. veracruzanus n. sp. in the shape of ovary and testes, which are oval in those species, while in H. mexicanus n. sp. the ovary is lobed and testes are elliptical or elongate. Haematoloechus mexicanus n. sp. differs from H. combesi, H. darcheni, H. floedae, H. leonensis, H. medioplexus, H. meridionalis, H. nicolasi, H. ocellati and H. parviplexus in the arrangement of the uterine loops. Haematoloechus medioplexus and H. meridionalis lack uterine longitudinal loops (Stafford, 1902; León-Regagnon et al. 2001), in H. combesi, H. floedae and H. leonensis they reach the level of the ovary (Williams & Coker 1967; Batchvarov & Bourgat 1974; León-Règagnon et al. 2005), in H. darcheni and H. ocellati they reach the level of the anterior testis (Combes & Knoepffler 1967; Gassmann 1975), in H. nicolasi and H. parviplexus they reach the level of the posterior testis (Irwin 1929; León-Règagnon 2017), while in H. mexicanus n. sp. they reach halfway between the posterior testis and the posterior end. In this new species there are frequently several short longitudinal uterine loops in the posttesticular region and at the level of testes, which are absent in the other species. Haematoloechus mexicanus n. sp. most closely resembles H. danbrooksi in the size of the ventral sucker and the presence of short diagonal or longitudinal uterine loops in the posterior end of body, but differs from that species in the shape of the ovary, which is oval or slightly bi-lobed in some specimens (León-Règagnon & Paredes-Calderón 2002) and deeply lobed in H. mexicanus n. sp. The arrangement of the uterus also differentiates these two species; while in H. danbrooksi the descending and ascending uterine loops often invade both sides of the body, in H. mexicanus n. sp. descending and ascending uterine loops form two lateral fields and rarely invade one another. Finally, the longitudinal uterine loops in the posterior end of the body are shorter in H. danbrooksi .Published as part of León-Règagnon, Virginia & Topan, Janet, 2018, Taxonomic revision of species of Haematoloechus Looss, 1899 (Digenea: Plagiorchioidea), with molecular phylogenetic analysis and the description of three new species from Mexico, pp. 251-302 in Zootaxa 4526 (3) on pages 269-272, DOI: 10.11646/zootaxa.4526.3.1, http://zenodo.org/record/261161
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